We remark that some models which are qualitatively different from the Kuramoto model can still be written in the form (REF ) with some modifications. For example, the Cucker-Smale model [1]}, [2]}
\({\left\lbrace \begin{array}{ll}\dot{x}_i = v_i,\\\dot{v}_i = \frac{\kappa }{N}\sum _{j=1}^N \psi (|x_i-x_j|)(v_j-v_i),\end{array}\right.}t>0,~i=1,\cdots ,N\) 
